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We work on the assumption that four major specialities or sectors of medical laboratory assays, comprising clinical chemistry, haematology, immunology, and microbiology, embraced by genome sequencing techniques, are routinely in use. Medical laboratory markers for inflammation serve as model: they are allotted to most fields of medical lab assays including genomics. Incessant coding of assays aligns each of them in the long lists of big data. As exemplified with the complement gene family, containing C2, C3, C8A, C8B, CFH, CFI, and ITGB2, heritability patterns/risk factors associated with diseases with genetic glitch of complement components are unfolding. The C4 component serum levels depend on sufficient vitamin D whilst low vitamin D is inversely related to IgG1, IgA, and C3 linking vitamin sufficiency to innate immunity. Whole genome sequencing of microbial organisms may distinguish virulent from nonvirulent and antibiotic resistant from nonresistant varieties of the same species and thus can be listed in personal big data banks including microbiological pathology; the big data warehouse continues to grow. [ABSTRACT FROM AUTHOR]

Antigen–antibody (Ab) interactions that lead to the formation of immune complexes (ICs) are subtle biochemical processes determining health or disease according to the outcome. Good laboratory practice (GLP)-acknowledged IC detection methods reveal that plasma levels of up to 15 μg/mL heat-aggregated immunoglobulin G (IgG) equivalents are normal, indicating the physiological role of ICs. Among the major variables that influence the equilibrium association constant Ka, are specificity and epitope density of the antigen, Ig class/subclass of the Ab, IC complement (C)-activating capacity, Fc receptor (FcR) interaction, and cytokine activation pattern. The Ka of antigen–Ab binding at ∼20°C ranges from low affinity (105) to high affinity (107–1011). Beneficial ICs serve to remove and/or neutralize infectious or toxic antigens, following an infectious attack in immune and vaccinated hosts. Circulating ICs are more prone for benefit than tissue-bound ICs, which reflect in situ formation and/or undesired deposition in tissues due to overflow from insufficient reticuloendothelial system (RES) removal. The classical textbook topic on ICs still holds true but is under revision because of the improved knowledge of effector systems, such as C, cytokine, and FcR apparatus. Therapeutic options to treat IC-associated diseases include intravenous immunoglobulins (IVIG) at their onset and monoclonal antibodies (mAb) directed at C activation products and/or cytokines. [ABSTRACT FROM AUTHOR]

Intramyocardial transplantation of skeletal myoblasts augments postinfarction cardiac function. However, poor survival of injected cells limits this therapy. It is hypothesized that implantation of myoblast-based scaffolds would result in greater cell survival. Rat skeletal myoblasts were seeded on highly porous polyurethane (PU) scaffolds (7.5 × 7.5 × 2.0 mm). The effect of several scaffold pretreatments, initial cell densities, and culture periods was tested by DNA-based cell count and viability assessment. Seeded PU scaffolds were implanted on infarcted hearts and immunohistology was performed 4 weeks later. Precoating with laminin allowed the most favorable cell attachment. An initial inoculation with 5 × 106 cells followed by a 15-day culture period resulted in optimal myoblast proliferation. Four weeks after their implantation in rats, numerous myoblasts were found throughout the seeded patches although no sign of differentiation could be observed. This myoblast seeding technique on PU allows transfer of a large number of living myoblasts to a damaged myocardium. [ABSTRACT FROM AUTHOR]

The science of blood groups has made giant steps forward during the last decade. Blood-group typing of red blood cells (RBCs) is performed on more than 15 million samples per year in Europe, today much less often for forensic reasons than for clinical purposes such as transfusion and organ transplantation. Specific monoclonal antibodies are used with interpretation on the basis of RBC agglutination patterns, and mass genotyping may well be on its way to becoming a routine procedure. The discovery that most blood group systems, whose antigens are by definition found on RBCs, are also expressed in multiple other tissues has sparked the interest of transplantation medicine in immunohematology beyond the HLA system. The one and only "histo-blood group" (HBG) system that is routinely considered in transplantation medicine is ABO, because ABO antigen-incompatible donor/recipient constellations are preferably avoided. However, other HBG systems may also play a role, thus far underestimated. This paper is an up-to-date analysis of the importance of HBG systems in the alloimmunity of transplantation and autoimmune events, such as hemolytic anemia. [ABSTRACT FROM AUTHOR]

BACKGROUND: In contrast to RBC transfusion, where ABO mismatch is potentially lethal, immunologic ABO matching has been considered less critical for PLTs. Nonetheless, PLTs bear ABO blood group antigens, some of them expressing very high levels. STUDY DESIGN AND METHODS: The expression of A antigen was investigated by flow cytometry on resting and stimulated human PLTs of 100 A and 10 O group donors, as well as on 17 PLT concentrates (PCs) after apheresis and daily during a 6-day storage, to determine possible changes in expression of A antigen on PLT surface. RESULTS: Considerable variation of A antigen expression on PLT surface of A[sub 1] group individuals was observed; A[sub 2] group PLTs could not be distinguished from O group PLTs. The variability of A antigen on A group PLTs also became evident on investigating PLT lysates by ELISA. A[sub 1] group PCs showed a significant increase of A antigen expression on their surface owing to apheresis (p = 0.001) and to storage (p = 0.0091). CONCLUSION: Apheresis and prolonged storage of A[sub 1] group PCs independently led to overexpression of A antigen on the PLT surface. This may make such PCs more susceptible to destruction by anti-A of O or B group recipients. [ABSTRACT FROM AUTHOR]

Galα1–3Gal (anti-Gal), a polyclonal so-called natural antibody (Ab), is present in large amounts in human serum not only as IgG-, but also as IgM- and IgA-isotypes. It has gained a particular interest in the context of xenotransplantation, because the endothelial pig cells express the terminal Galα1–3Gal determinant on several adhesion molecules. Little is known of it's function and direct examination of the structure of the Ig genes responsible for coding anti-Gal is lacking. We used the technique of isoelectric focussing (IEF)/affinity immunoblotting for direct analysis of the clonal distribution and spectrotype analysis of IgM- and IgG anti-Gal. By single cell analysis of magnetic bead and fluorescent-activated cell sorter (FACS) isolated mature anti-Gal bearing human B cells from whole blood we analyzed the VH gene families involved in anti-Gal production. Oligoclonal and individually distinct IgG banding patterns were found with isoelectric points between 4 and 9. IgM spectrotypes revealed to be more uniform with a polyclonal banding pattern of more than 12 bands at a pH between 4.7 and 7. IgG- and IgM-banding patterns over a period of 6 months remained unchanged. Single cell polymerase chain reaction (PCR), with all family specific primers, revealed the use of the VH 2f gene family for the IgG2 isoptype. The differences found in the spectrotype banding patterns of IgG and IgM could be explained by the suggestion that anti-Gal IgM were produced by the use of unmutated germline genes and the possibility of the absence of somatic mutations. The greater clonal heterogeneity in the IgG population could be explained by somatic hypermutations during the switch from IgM to IgG. The use of this VH 2f gene family, which is also involved in the generation of Abs against bacterial pathogens, could mean that this is a predominant region used for the generation of such natural occurring antibodies. [ABSTRACT FROM AUTHOR]

Deals with the treatment of thrombocytopenia in non-viral cirrhosis patients and hepatotropic virus-infected patients. Implication of persistent viraemia; Causes of liver failures that were analyzed in the patients.

Abstract: Therapeutic plasma exchange (PE) has been used for three decades in the treatment of autoimmune disease. Its mechanism of action hinges on a profound modulation of the immune system which is only partially understood. Removal of circulating immune complexes, immunoglobulins, and complement components play a role. Moreover, the substitution of plasma components like anti-idiotypic antibodies and immunoglobulins targeted against a host of antigens may add to its beneficial effects. Recently, intravenous administration of immunoglobulins was found to mimic the effects of PE in certain diseases. In fact, downregulation of Fc receptors, modulation of the complement activation, and anti-idiotypic downregulation of primary autoantibodies are mechanisms held to be responsible for its immunosuppressive effects.This article summarizes the effects of both treatment modalities, discusses their pros and cons, and makes differential therapeutic suggestions for the clinician of which to use in various autoimmune diseases. [ABSTRACT FROM AUTHOR]

Abstract: Extracorporeal immunoabsorption for removal of anti-Galα1–3Gal (anti-Gal) antibodies in putative pig-to-human xenotransplantation is considered a major prophylactic measure to avoid hyperacute and acute vascular rejections. However, the efficacy of the procedure does depend on choosing the appropriate oligosaccharide epitopes for the binding of human anti-Gal. The synthetic oligosaccharides Galα1–3Gal (B-disaccharide, Bdi) and Galα1–3Galβ1–4Glc (‘type 6’ trisaccharide, Tri6), covalently coupled to Sepharose via polyacrylamide (Sorbents Bdi and –Tri6, respectively), as well as a mixture thereof (Sorbent Mix), were examined for their efficacy to absorb anti-Gal from 20 human serum samples. Sorbent Bdi removed 81% of anti-Gal IgM and 85% of –IgG when assessed on Bdi by ELISA, but only 49% of IgG and 75% of IgM when assessed on Tri6. Sorbent Tri6 and –Mix showed significantly better absorption capacities in so far as Sorbent Tri6 removed 65% of anti-Gal IgM and 80% of –IgG as assessed on Bdi and 85% of IgM/87% of IgG when tested on Tri6, and Sorbent Mix absorbed > 90% anti-Gal of both isotypes of either specificity. Direct hemagglutination of rabbit erythrocytes (ER) was reduced by 75% (median value, range 0–94%) and the median cytotoxicity to PK15 target cells by > 94% after absorption on Sorbent Mix. Neither the decrease in ER agglutination titers nor the reduction of PK15 cytotoxicity revealed significant differences between the three immunoabsorbents tested. The large variation ranges of absorption efficacies within the 20 tested sera suggest that “tailor-made” immunoabsorption treatments may be needed for putative xenotransplant recipients. [ABSTRACT FROM AUTHOR]

Background: Erythropoietin (Epo), a growth factor produced by the kidney, is important in heart failure patients to promote oxygen delivery to tissues. Seventy-two chronic heart failure (CHF) patients at our outpatient clinic were subjected to morning serum Epo-level measurements and classified according to NYHA criteria.Results: Forty-eight patients of classes III and IV had a significantly elevated serum Epo-level of 42.9+/-40.3 mIU/ml (mean+/-1 S.D.) when compared to the mean level of 24 patients of classes I and II who had a normal range mean value of 13.4+/-6.2 mIU/ml (P<0.05). Patients on angiotensin-converting enzyme (ACE) inhibitors showed a trend towards lower serum Epo-levels compared to patients treated with angiotensin-II type-1 receptor antagonists (AT(1) antagonists) (levels: 33.3+/-35.6 mIU/ml and 43.6+/-38.1 mIU/ml). This trend did not, however, reach statistical significance (P=0.36).Conclusion: We suggest that a desirable Epo increase in class III and IV CHF patients could be achieved by either recombinant human Epo administration or, possibly, by appropriate selection of the concomitant medical therapy. A large prospective study shall investigate the possible advantage of AT(1) antagonists over ACE-inhibitors with regard to Epo effect. [ABSTRACT FROM AUTHOR]

Buonomano R, Tinguely C, Rieben R, Mohacsi PJ, Nydegger UE. Quantitation and characterization of anti‐Galα1–3Gal antibodies in sera of 200 healthy persons. Xenotransplantation 1999; 6:173‐180. © Munksgaard, Copenhagen Abstract: The natural occurrence of complement‐activating anti‐Galαl–3Gal antibodies (anti‐Gal) in human serum is considered as a major obstacle to xenotransplantation. In this study we determined anti‐Gal in sera of 200 healthy volunteers (100 male, 100 female) of different age groups using an IgG‐ and IgM‐isotype specific ELISA. In addition, we used a direct hemagglutination test involving rabbit erythrocytes (ER), which are known for abundant surface expression of the Galα1–3Gal antigen. The measured arbitrary ELISA units (U) for anti‐Gal ranged from 5 to 204 U (77 ± 47; mean ± 1 SD) for IgM, and from 1 to 162 U(73 ± 32) for IgG. Anti‐ER hemagglutination titers were between 1: 65536 and 1: 64 (mean 1: 703), with 75% of all serum samples being in the range of 1: 8192–1: 512. Specificity of the tests was determined by immunoabsorption of anti‐Gal on Sepharose‐coupled synthetic Galα1–3Gal antigen, which reduced ELISA as well as agglutination titers by 90% or more. Overall, inter‐individual differences of both anti‐Gal ELISA values and ER agglutination titers exceeded age‐, gender‐, or ABO‐type related changes. A tendency was found to higher anti‐Gal IgM values in women than in men (P < 0.005 by Student’s t‐test), whereas the gender‐difference for anti‐Gal IgG or ER titers was not significant. Application of the anti‐Gal ELISA as well as the ER agglutination assay for pre‐transplant screening of potential pig xenograft recipients is discussed. [ABSTRACT FROM AUTHOR]